Field of the Invention
The present invention relates to a liquid coating device that coats liquid on a surface of a matrix which has a long length and is made of metal, resin or the like by dipping the matrix into the liquid. It particularly relates to a liquid coating device that coats flux on a surface of solder formed as a matrix having a long length. It also particularly relates to a liquid coating device that coats liquid such as paint or the like on a surface of a matrix which is made of metal, resin or the like.
Description of Related Art
The following will describe the liquid coating device that coats liquid on a surface of a matrix which has a long length and is made of metal, resin or the like by dipping the matrix into the liquid, and a flux applying device used for soldering and the solder on which the flux is applied when using the liquid coating device, as an example of the object on which the liquid is coated when using the liquid coating device.
Flux used for soldering is applied to solder or the like through a flux applying step as a preliminary treatment of a soldering processing process. The flux has such effects that it chemically removes any metal oxides on a surface of the solder and a surface of the metal to be soldered; it prevents the metal surface from being again oxidized during a period of heating time in a soldering step; it reduces surface tension of the solder to improve wettability thereof. After the soldering, the flux forms intermetallic compounds between the solder and the metal to be soldered, thereby obtaining a strong joint therebetween.
Flux coating preform solder in which the flux is applied to a surface of the solder formed so as to have a long length has been proposed. Since in the flux coating preform solder, the flux has been previously coated before the soldering, it is possible to omit a flux applying step in the soldering time. Since the flux coating preform solder has a long length, it can be processed so as to be a suitable form such as a pellet, a washer and a disk, thereby allowing it to be applied to a various kinds of mounting technologies.
The coated flux in the flux coating preform solder is desirable to be almost uniformly applied on a surface of the solder. This is because if the flux is not uniformly applied on the surface of the solder, this becomes any cause of failure in the soldering.
Japanese Patent Application Publication No. S54-075452 discloses a flux applying apparatus in which a solder line is passed through a tank containing molten flux and rollers pull the solder line through a die so that the die adjusts an amount of flux applied to the solder line on an assumption that the flux is applied to the surface of the solder line just before the soldering.